head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Pure Mechanics
Landmark FPS built on physics puzzles and tight gunplay.

Execution · Pure Mechanics
Top-down run-and-gun testing aim and memorised level knowledge from a movie license.
Half-Life 2 leans Execution (Pure Mechanics); True Lies leans Execution (Pure Mechanics).
True Lies leans a little harder on execution, though the gap is small.
Half-Life 2
Gravity gun and shooting demand precision.
True Lies
Top-down aim and dodging carry every firefight
Half-Life 2 leans a little harder on reads, though the gap is small.
Half-Life 2
Combine AI scripted, non-adaptive.
True Lies
Goons follow simple fixed attack scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Half-Life 2
Almost no randomness.
True Lies
Enemy placements repeat identically each run
True Lies leans a little harder on optimization, though the gap is small.
Half-Life 2
Linear progression with no builds.
True Lies
Learning level layouts, hostage spots and ammo caches
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.